اشترك بالحزمة الذهبية واحصل على وصول غير محدود شمرا أكاديميا
تسجيل مستخدم جديدDisappearance of partonic collectivity in $sqrt{s_{NN}}$ = 3 GeV Au+Au collisions at RHIC
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We report on the measurements of directed flow $v_1$ and elliptic flow $v_2$ for hadrons ($pi^{pm}$, $K^{pm}$, $K_{S}^0$, $p$, $phi$, $Lambda$ and $Xi^{-}$) from Au+Au collisions at $sqrt{s_{NN}}$ = 3 GeV and $v_{2}$ for ($pi^{pm}$, $K^{pm}$, $p$ and $overline{p}$) at 27 and 54.4 GeV with the STAR experiment. While at the two higher energy midcentral collisions the number-of-constituent-quark (NCQ) scaling holds, at 3 GeV the midrapidity $v_{2}$ is negative for all hadrons and the NCQ scaling is absent. In addition, the midrapidity $v_1$ slopes for almost all observed hadrons are found to be positive, implying dominant repulsive baryonic interactions. The features of negative $v_2$ and positive $v_1$ slope at 3 GeV can be reproduced with a baryonic mean-field in transport model calculations. These results imply that in 3 GeV Au+Au collisions, the medium is characterized by baryonic interactions.
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